Preheat oven to 400 degrees. Line a baking sheet with parchment paper; set aside.
Sprinkle work surface with sugar. Place puff pastry on top of sugar. Sprinkle top of puff pastry with sugar. Roll puff pastry into a 12-by-14-inch rectangle. Using a round cookie cutter, cut six 4 1/2-inch rounds; transfer to prepared baking sheet.
With a sharp knife, score each pastry, making curved lines every 1/2-inch from the center out towards the edges, to resemble a pinwheel. Transfer baking sheets to a refrigerator until well chilled, at least 30 minutes.
In a small bowl, beat together egg yolk and cream. Brush tops of chilled pastry rounds, leaving a 1/4-inch border around the edge; take care not to let any egg mixture drip over cut edges, as it will prevent pastry from puffing evenly. Sprinkle each round with 2 teaspoons sugar. Bake until crisp and caramelized, 15 to 18 minutes. Let cool on baking sheet.